Advice needed on replacing spindle bearings in Enco Mill Drill

Advice needed on replacing spindle bearings in Enco Mill Drill

Post by Michae » Thu, 01 Apr 2004 12:56:19



  I have a well used Enco Mill Drill which is made by Rong Fu in Taiwan.  I
think it's the model RF-20.  The spindle on it has a bit of play and tends
to produce lots of harmonics and chatter when boring or using the side of an
endmill to cut.  I don't know much about these so this may be something that
can be addressed by turning a spanner, or maybe it needs new spindle
bearings.  If anyone has had to correct this on one I'd really appreciate
any input on what the cause usually is and how to go about fixing it.
Thanks, Michael.
 
 
 

Advice needed on replacing spindle bearings in Enco Mill Drill

Post by Bob Powel » Thu, 01 Apr 2004 14:34:56



Quote:
>   I have a well used Enco Mill Drill which is made by Rong Fu in Taiwan.
I
> think it's the model RF-20.  The spindle on it has a bit of play and tends
> to produce lots of harmonics and chatter when boring or using the side of
an
> endmill to cut.  I don't know much about these so this may be something
that
> can be addressed by turning a spanner, or maybe it needs new spindle
> bearings.  If anyone has had to correct this on one I'd really appreciate
> any input on what the cause usually is and how to go about fixing it.
> Thanks, Michael.

I have the identical machine, made in 1992.

I think the spindle bearings are ordinary ball bearings, like standard
sealed electric motor bearings - nothing ***.  In the realm of $50 for an
identical Chinese replacement.

That said, the quill bore is likely to wear faster than the bearings.  Do
you do all side cutting with the quill securely locked?  When boring, the
quill lock should be cranked enough to drag.   Accelerates wear but improves
the finish.

It's also possible that the upper spindle bearings are at fault, as they
take the side load of the belt but are not as beefy as the spindle bearings.

The table ways/gibs are also pretty rough, I found it difficult to get a
perfect gib adjustment and so have always cranked the gib locks until the
table drags a bit when making a finish cut.  Again, accelerates way wear but
improves finish.

Goes without saying whichever axis is not moving should have its gib locks
tight.  For boring, both axes.

Bob

 
 
 

Advice needed on replacing spindle bearings in Enco Mill Drill

Post by Bob Powel » Thu, 01 Apr 2004 15:37:35



Quote:


> >   I have a well used Enco Mill Drill which is made by Rong Fu in Taiwan.
> I
> > think it's the model RF-20.  The spindle on it has a bit of play and
tends
> > to produce lots of harmonics and chatter when boring or using the side
of
> an
> > endmill to cut.  I don't know much about these so this may be something
> that
> > can be addressed by turning a spanner, or maybe it needs new spindle
> > bearings.  If anyone has had to correct this on one I'd really
appreciate
> > any input on what the cause usually is and how to go about fixing it.
> > Thanks, Michael.

> I have the identical machine, made in 1992.

> I think the spindle bearings are ordinary ball bearings, like standard
> sealed electric motor bearings - nothing ***.  In the realm of $50 for
an
> identical Chinese replacement.

> That said, the quill bore is likely to wear faster than the bearings.  Do
> you do all side cutting with the quill securely locked?  When boring, the
> quill lock should be cranked enough to drag.   Accelerates wear but
improves
> the finish.

> It's also possible that the upper spindle bearings are at fault, as they
> take the side load of the belt but are not as beefy as the spindle
bearings.

> The table ways/gibs are also pretty rough, I found it difficult to get a
> perfect gib adjustment and so have always cranked the gib locks until the
> table drags a bit when making a finish cut.  Again, accelerates way wear
but
> improves finish.

> Goes without saying whichever axis is not moving should have its gib locks
> tight.  For boring, both axes.

> Bob

Sorry, I just RTFM'd a bit late.  Oops.

According to the manual they are grease-packed taper roller bearings, the
upper is a 30205J and the lower is an E30206J.

Adjusted by a pair of locknuts at the top of the quill.

The manual says to loosen the bearings if they run too hot, tighten if the
surface finish is "rough".  It doesn't say how, but it looks like you remove
the rack pinion (i.e. the quill feed shaft) and the quill just drops out the
bottom of the head casting.  I don't know if you can get to the bearings via
any of the access plates, may just have to remove the quill.

I can say from other experience, if the quill doesn't heat up when running
at top speed, the bearings are too loose.

Mine has behaved so consistently, I never would have guessed taper roller
bearings.

Bob

 
 
 

Advice needed on replacing spindle bearings in Enco Mill Drill

Post by Dick Morri » Fri, 02 Apr 2004 11:08:37


If you don't have a manual to look at, the last time I looked a number
of the Enco manuals could be downloaded from their web page. It's at
"goenco.com" or something like that.

Dick Morris
Anchorage, Alaska

On Tue, 30 Mar 2004 21:56:19 -0600, "Michael"

Quote:

>  I have a well used Enco Mill Drill which is made by Rong Fu in Taiwan.